Cut-off-valve gear



Witnesses.

(No Model.) V A I. A. GARDNER. GUT-OFF VALVE GEAR. No. 291,181. Patented Jannl, 1884.

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' UNITED STATES PATENT Br en.

FREDERICK A. GARDEER, OF BUFFALO, NEW YORK, ASSIGNOR OF ONE-HALF TO DUNBAR & SON, OF SAME PLACE.

CUT-OFF-VALVE 'GEAR.

SPECIFICATION forming part of Letters Patent No. 291,181, dated January 1, 1884,

Application filed April 20, 18825. (No model.)

To all whom it may concern.-

Be it known that I, FREDERICK A. GARD- NEH, a subject of the Queen of Great Britain, residing ill-Buffalo, in the county of Erie and State of New York, have invented certain new and useful Improvements in Automatic Out- Off-Valve Gear, of which the following is a specification. I y I The object of my invention is toprovide the means for admitting steam to theengine in proportion to the power required that is, as the power to be overcome by the engine becomes greater, the amount of steam admitted thereto is increased and as the. power to be overcome becomes less the amount of steam is cut off in like proportion-eall of which will be fully and clearly hereinafter shown and described, by. reference to the accompanying drawings, in which- Figure 1 is a vertical central section through the device in line X X, Fig. 3, all being in section,except the central shaft and the reversingbar and its connections. Fig. 2 is a front elevation of aportion of the device. Fig. 3 is a back view, showing a front or face view of the eccentric. Fig. 4 is avcrtical central section through the eccentric and frame. Fig. 5 isaback end view of the same. Fig. 6 is aside elevation of a portion of the front of the device, show o ing a portion broken away, so as to expose the indicator. Fig. 7 is vertical longitudinal central section through the eccentric-supporting frame and the case within which it is fastened. Fig. 8 is an end view of the same. 3 5. Fig. 9 isa front view of the governor-weights and connections; and Fig. 10 represents a top view of the eccentric and frame, showing the diagonal slot. I

a is the case; a, the support upon which the eccentric rocks on the pin or bar a a represents the eccentric. It is a hollow orgrooved eccentric provided with a curved piece, a nicely fitted in the groove a", (see Fig.- 3,) the valve-stem being connected in any well-known way to a pin, 1). The valvestem (which passes across the face of the eccentric and is secured so as toallow only a reciprocating movement in the line of its length, substantially as shown in my patent dated March 30, 1880, No. 226,055) is 0011- nected by the pin 12 to the curved piece at one end, and the opposite end is connected in any well -known way to the valve, the arrangement being such that the curvedpiece a which is placed in the eccentric or groove a moves as the eccentric turns toward and from the center, and thereby imparts the required reciprocating movements to the valve. If more than one cylinder be used, then there would be as many of the pieces a as there are cylinders. Forinstance, asingle-cylinder engine would require but one, while athre'e-cylinder engine would require three The eccentric is provided with openings 0 c, sufficiently wide to allow it to rock the required distance for reversing the engine, and is provided with a diagonal slot, 0", into which the friction-roller b on the reversing-bar b is fitted. The reversingbar is kept from turning in the supporting-piece a by means of a feather or its equivalent, which iits into a groove, 0. (Shown in Fig. 8.) It is provided with a spiral spring, I), which presses against the head 0 of the reversing-bar, and the opposite end is kept in place by the tubular piece I), securely fastened to the end of the case a by means of pins 0*. The collar (1, for holding the governorweights d, is also secured in place by the pins 0*. The governor-weights are pivoted to the collar d by means of pins d, and are each provided with slotted eXtension-pieces d ()11 the end of the reversingbar on each side, directly'opposite each other, are two pins, d, which enter the slots (1 in the extension-pieces. At the end of the reversingbar is a bolt, 6, which is held forward against it by a spiral spring,c. The governor-weights are provided with a spring, 6", which assists in holding them forward; but in some cases this spring may be dispensed with. The tension or force of the spring 6' is regulated by the thumb-screw e and jam-nut e. The governor-weights and connections are inclosed within a case, 6". An indicator, f, is arranged on the outside of the case 6, and is connected to a strip of metal, f, arranged to slide in a groove or slot in the tubular portion f of the case 0 (See Figs. 1, 2, and 6.) The object of the indicator is to show at all times, while the engine is running, the point at which steam is cutoff, (see index f" in Fig. 6.)

f is the opening through which steam is admitted to the engine; but this flue may be arranged in any other convenient way.

The engine crank-sliaftf" is secured to the eccentric-supporting piece a by means of a pin, 5/.

The operation of the invention is as follows: The case a, the eccentric and all its connec tions. the reversingbar, and the governorweights all revolve in the bearing 9. The case c with its thumb-screw c and janrnut e, are rigidly fastened to the portion g", and remain stationary. The crank-shaftf being rigidly attached to the device, turns everything with it, except the parts mentioned above, and in proportion to the speed the governor-weights are forced back toward the points 8'. (See Fig. 1.) This operation brings the reversing-bar forward, and in proportion as it moves forward it turns the eccentric on its center pin, a, by means of the diagonal slot and the friction-roller, as before 1ne11- tioned, and cuts off the steam more or less according to its movement one way or the other. and atthe same timeit moves theindicator-hand and indicates the point at which the steam is cut off. The governor weiglits draw the reversing-bar in one direction against the force of the springs I) and 0, so as to turn the eccentric one way, and the springs move it in the reverse direction as the motion becomes slower, so as to turn the eccentric the opposite way. The thumb-screws e" e*regulatc the pressure of the spring 0 against the head of the reversing-bar. A further object of the thumbscrews is to act as a speederthat is, the farther the thumb-screw c is forced in the greater will be the speed of the engine, be cause it increases the force to be overcome by the governor-weights. In some cases the case 0", for inclosing the governor-weights, may be dispensed with, or the governor-weights may be connected with the reversing-bar at any point between its present position and the opposite end, and the position of the ease e" may be changed in accordance therewith without changing the nature of this invention.

I have an application fora patent now pending for certain improvements in valve-gear, filed March 30, 1883, serial number of application 89,979, in which some portions of the valve-gear represented in this case are shown. I therefore do not claim anything in this case relating to the valve-gear shown in said application; but

"\Vhat I do claim isl. The combination of the eccentric having a diagonal slot, and arranged on the center bar, a", the reversingbar provided with africt-ion-roller, a spring for operating it one way, and the governor-Weights for operating it the other way, all connected for joint operation, substantially as described.

2. The combination, substantially as de scribed, of the bolt 0, springs, and thumb-screw 0*, for the purposes specified.

3. The case a, the pivoted eccentric having the diagonal slot, the reversing-bar provided with the friction-roller and the spring b, the governor-weights connected thereto, substaa tially as specified, and the case 0, for the purposes described.

FREDERICK A. GARDXER.

Witnesses:

J. M. CALDwnLL, James Saxosrnn. 

